[[UIDevice currentDevice] orientation] always null

Question

As per the title. Calling [[UIDevice currentDevice] BeginGeneratingDeviceOrientationNotifications] has no effect.

DidRotateToInterfaceOrientation etc events are working fine, but I need to be able to poll the device orientation arbitrarily.

How can I fix/do this?

The long story: I have a tab application with a navigation controller on each tab. The root view of tab number one is a graph that goes full screen when the orientation changes to landscape; however this needs to be checked whenever the view appears as the orientation change could have occurred elsewhere, so I was hoping to poll the orientation state whenever this view appears.

Answer 1

Wouldn't [[UIDevice currentDevice] orientation] give you the current orientation state? You could check for this in your viewWillAppear method of the view controller that wants to poll.

Edit: Other than that, there are various ways to get the current orientation, such as using the statusBarOrientation property in UIApplication, or interfaceOrientation property in UIViewcontroller.

Answer 2

seems like a silly question, but isn't it

beginGeneratingDeviceOrientationNotifications

( lower case b ) ...

Answer 3

UIDevice's notion of orientation seems to be only available on actual devices. The simulator seems to always return 0 here, regardless of whether the notifications have been enabled as the docs suggest. Irritatingly inconvenient, but there you go.

I find this works fine on the actual device:

    [[UIDevice currentDevice] beginGeneratingDeviceOrientationNotifications];
    NSLog(@"orientation: %d", [[UIDevice currentDevice] orientation]);
    [[UIDevice currentDevice] endGeneratingDeviceOrientationNotifications];